Geographical distribution of the giant honey bee Apis laboriosa Smith, 1871 (Hymenoptera, Apidae)

Worldwide pollinator declines have dramatically increased our need to survey and monitor pollinator distributions and abundances. The giant honey bee, Apis laboriosa, is one of the important pollinators at higher altitudes of the Himalayas. This species has a restricted distribution along the Himalayas and neighbouring mountain ranges of Asia. Previous assessments of its distribution, published more than 20 years ago, were based on museum specimens. Since then, 244 additional localities have been revealed through field trips by the authors, publications, and websites. We present a revised distribution for A. laboriosa that better defines its range and extends it eastward to the mountains of northern Vietnam, southward along the Arakan Mountains to west-central Myanmar, into the Shillong Hills of Meghalaya, India, and northwestward in Uttarakhand, India. This species is generally found at elevations between 1000–3000 m a.s.l.. In northeastern India A. laboriosa colonies occur during summer at sites as low as 850 m a.s.l. and some lower elevation colonies maintain their nests throughout the winter. Finally, we report three regions in Arunachal Pradesh, India, and nine locations in northern Vietnam, where we observed workers of A. laboriosa and A. dorsata foraging sympatrically; their co-occurrence supports the species status of Apis laboriosa.

The reasons for the different nest shapes of Megapis bees

Over a 37-year period, we observed 1011 active bee nests and abandoned combs of Apis dorsata and Apis laboriosa in Nepal, India, the Philippines, and Bhutan. This article focuses on the reasons for the different shapes of the nests. We discovered that differing ambient conditions were the reasons for the following three shapes of symmetrical nests: vertical semi-ellipse, semicircle, and the horizontal semi-ellipse. We noted that asymmetrical nests were constructed when there was lack of space to extend the comb equally in both external directions. An asymmetrical nest also appeared when remnants of a previous comb remained on one edge of the nest. Convex nests were constructed to avoid excess sun exposure. Concave nests appeared as a result of low temperatures during the night and part of the day (Nepal). An L-shape nest was constructed when there was lack of space available to extend the nest in a straight direction. The shape of the nests also determines the way the combs fall.

Swarming and Migration of Apis dorsata and Apis laboriosa Honey Bees in India, Nepal and Bhutan

Swarming and Migration ofApis dorsataandApis laboriosaHoney Bees in India, Nepal and BhutanThe migratory open air nestingApis dorsataandApis laboriosahoneybees migrate at least twice a year. DNA genotyping showed that the same swarms return to their natal nesting sites. We examined 23 nesting sites in Nepal, India and Bhutan, on which 587 colonies ofA. dorsataandA. laboriosanested. The results showed that the frequency of the periodic mass flights (PMF) performed by the colonies is a good indicator of the status of current colony performance. During the swarming period, both,A. dorsataandA. laboriosaissue several swarms. In some colonies, so many bees swarmed out, that those remaining in the maternal colonies did not cover the combs. After the rest of the brood emerged, all the bees of such colonies abscond during the swarming period. Thus, absconding appeared in results of total out swarming. The swarms do not migrate directly to the seasonal alternative nesting sites, but establish new colonies in the areas around. After environmental conditions deteriorate, all the bees with their queens abscond and migrate to alternate seasonal nesting sites. The next season, the swarms do not return to their original reproductive natal sites, but to those sites they occupied the previous season lately, where from they absconded.